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Old 02-21-2017, 10:34 AM   #1
cpnbnanamn
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Hazard lights diagram?

Anyone have the hazard light wiring from the relay ~> out? Just discovered that my front flashers are working when the hazard lights are on, but the rear ones aren't. Yeah.. need to fix that. Just need a starting point.
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Old 02-23-2017, 11:14 AM   #2
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Re: Hazard lights diagram?

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Originally Posted by cpnbnanamn View Post
Anyone have the hazard light wiring from the relay ~> out? Just discovered that my front flashers are working when the hazard lights are on, but the rear ones aren't. Yeah.. need to fix that. Just need a starting point.
By relay I assume you mean the flasher in the fuse panel. If so, there is a 16 gauge brown wire from the fuse panel to the half moon connector on the steering column, that sends power to the hazard switch in the turn signal switch.
The hazard switch sends power to the front and rear lights through the same wires that the turn signals use. LT blue, Dark blue, for the fronts and Yellow and Dark green for the rears.

Do your rear signals work? If they do then you aren't getting power through the hazard switch and the contacts may be dirty or they may be damaged and you'll have to replace the switch.


Here is a diagram. The half moon connector is on the upper right and the 16 gauge brown wire is in the middle next to the purple wire. The brown wire is hot all the time and does not need power from the key switch like the turn signals do.

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Old 02-23-2017, 11:45 AM   #3
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Re: Hazard lights diagram?

The rear turn signals and brakelights do work, and so do the front parking lights when the hazards are on. It seems that the issue is after the switch, and I am trying to figure out where.
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Old 02-23-2017, 02:19 PM   #4
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Re: Hazard lights diagram?

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Originally Posted by cpnbnanamn View Post
The rear turn signals and brakelights do work, and so do the front parking lights when the hazards are on. It seems that the issue is after the switch, and I am trying to figure out where.
It sounds to me like your hazard switch is bad. Your wiring circuits are good but you aren't getting power to them from the hazard switch. You must be getting power to the hazard switch if the fronts flash, but not the rears. And you must be getting power to the fronts through the switch because the fronts are flashing.

Unplug the half moon connector and do a continuity check between the brown wire in the connector and the dark green wire. Look for zero ohms and then do the brown, and yellow wires looking for zero ohms. This is on the wires that go to the turn signal switch.

Your wires in the harness might not be the same colors on both sides of the half moon connector, so you might have to match them up with the wires on the other side of the connector, that comes from the fuse panel. When you check the wires be sure to pull the hazard switch on. You can also check the two blue wires too, and they should have zero ohms since the fronts do work.,

Here's a picture. notice that all the wire colors don't match, but you wires should because your lights work. If you are confused then just post back and I'll clarify it more for you.

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Old 08-24-2019, 02:24 PM   #5
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Re: Hazard lights diagram?

VetteVet - just curious about your discussion concerning the continuity check of the switch harness where you mention to "...be sure to pull the hazard switch on." To turn the hazard lights on in my truck you push the hazard switch on. Either way, I understood you to mean the hazard switch had to be on for a proper continuity check and that's the way I checked it. Are there versions where you pull the hazard switch on? Again, thanks for the help.
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Old 08-25-2019, 11:35 PM   #6
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Re: Hazard lights diagram?

Yes you are correct that the switch has to be turned on whether it is pushed in or pulled out. I was probably thinking of one of my other vehicles.
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Old 02-23-2017, 08:14 PM   #7
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Re: Hazard lights diagram?

Found the issue. Bad switch. Everytime I wiggle the switch, either they all (rears) come on, or just one comes on, or they all go out. Thanks for the help!!
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Old 02-24-2017, 01:36 PM   #8
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Re: Hazard lights diagram?

Quote:
Originally Posted by cpnbnanamn View Post
Found the issue. Bad switch. Everytime I wiggle the switch, either they all (rears) come on, or just one comes on, or they all go out. Thanks for the help!!
From you very good description of your symptoms I was pretty sure it had to be the switch. Good job. VV
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Old 02-24-2017, 01:42 PM   #9
cpnbnanamn
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Re: Hazard lights diagram?

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From you very good description of your symptoms I was pretty sure it had to be the switch. Good job. VV
No, man.. Thank you! I greatly appreciate the help!
I was hoping to see the wiring diagram between the relays and the switch, and the one that's published doesn't show it. I really appreciate all the help and responses.

-Roger
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Old 03-18-2018, 09:01 PM   #10
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Re: Hazard lights diagram?

Thank you VetteVet. Your instructions on this helped me diagnose my problem as well.
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Old 03-18-2018, 11:15 PM   #11
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Re: Hazard lights diagram?

Quote:
Originally Posted by cpnbnanamn View Post
No, man.. Thank you! I greatly appreciate the help!
I was hoping to see the wiring diagram between the relays and the switch, and the one that's published doesn't show it. I really appreciate all the help and responses.

-Roger
Quote:
Originally Posted by jeff_wilson70 View Post
Thank you VetteVet. Your instructions on this helped me diagnose my problem as well.
Thanks guys I'm always glad to help.
Welcome to the forums Jeff.
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Old 08-23-2019, 03:27 PM   #12
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Re: Hazard lights diagram?

Thanks for this thread. It helped me troubleshoot my flasher system.
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Old 08-24-2019, 01:32 PM   #13
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Re: Hazard lights diagram?

This forum is the best one on the net.
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Old 08-24-2019, 01:47 PM   #14
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Re: Hazard lights diagram?

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This forum is the best one on the net.
I think so by far. Thanks for your service also.
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